This invention relates to split housing axial turbines and, more particularly, to a locking device to facilitate insertion and removal of a diaphragm upper half, secured in the upper portion of the turbine housing, when assembling and disassembling the turbine.
The diaphragms located between the turbine wheels mounted on a rotor enclosed within the horizontally split housing of an axial turbine are also split into two parts. Thus, the turbine has a horizontal shaft and the turbine housing and the diaphragms are divided along a horizontal axial section, with each portion of a diaphragm arranged in a respective portion of the turbine housing. The diaphragms are mounted relatively loosely in slots in the turbine housing, in order to allow for thermal expansion and contraction of the housing and the diaphragms in relation to one another, and are preferably secured against rotation in the slots. Generally, no special joint between the two halves of a diaphragm is required. The lower portion of a diaphragm is placed in a corresponding slot in the lower portion of the turbine housing, while the upper portion of the diaphragm is secured in some manner in the upper portion of the housing until the housing halves and the diaphragm halves been properly aligned and joined together.
The upper portion of a diaphragm may be secured to the upper portion of the turbine housing for alignment with the diaphragm bottom portion upon joining of the housing portions by means of pins carried in the turbine housing inner wall. These pins project into corresponding recesses in the diaphragm outer peripheral surface. However, the positioning of the diaphragm upper portion and the turbine housing upper portion is not easily accomplished due to the presence of these projecting securing pins which interfere with convenient placement. Thus, the present arrangements do not permit the easy insertion and removal of the diaphragm upper portion when assembling and disassembling the turbine.